Optical scanning probe devices have been developed in recent years with which optical information about an examination site is obtained by transmitting light generated by a light source device through an optical fiber, emitting this light from the tip of the optical fiber and shining it on the examination site, and scanning the focal position back and forth.
A conventional example of this is U.S. Pat. No. 5,120,953.
This conventional example discloses an endoscope that gives an enlarged view of the tissue at the examination site. This conventional example also discloses the technique of scanning the tip of an optical fiber with an actuator, and scanning the focal point with a condensing lens disposed in front of this actuator. The scanning of a focal point with a scanning mirror has also been disclosed in U.S. Pat. No. 5,742,419.
However, when optical fiber scanning is performed by scanning the optical fiber tip end with respect to the lens, the optical fiber, which is disposed along the optical axis of the lens, deviates from this optical axis, making it difficult to achieve high resolution.
Accordingly, the present applicant proposed an optical fiber and (object) lens scanning type of optical scanning probe with which the (object) lens is scanned along with the optical fiber tip in such a case.
With this type, the optical fiber tip disposed along the optical axis of the lens does not deviate in its relative position from the lens when scanned, so in principle the aperture number can be larger and higher resolution is possible.
On the other hand, because optical fiber and lens scanning requires the scanning of both the optical fiber tip and the lens with an optical fiber and lens scanning type of optical scanning probe, an optical fiber scanning type is advantageous in that faster scanning is possible.
Accordingly, when this apparatus is used inside the body, for example, if an optical fiber scanning type can be used if the site being observed is one that moves, such as the heart, and if an optical fiber and lens scanning type, which affords higher resolution, can be used if the site being observed does not move, then the resulting system will be extremely convenient.
The present invention was conceived in light of the above situation, and it is an object thereof to provide an optical scanning probe system with which it is possible to use the optical scanning probe best suited to the site being examined.
Another object is to provide an optical scanning probe with which higher resolution can be obtained.